/*
 * Copyright (c) 1998, 2020, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package sun.security.util;

import java.io.PrintStream;
import java.math.BigInteger;
import java.util.HexFormat;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
import java.util.Locale;
import sun.security.action.GetPropertyAction;

A utility class for debugging.
Author:
Roland Schemers/**
 * A utility class for debugging.
 *
 * @author Roland Schemers
 */
public class Debug {

    private String prefix;

    private static String args;

    static {
        args = GetPropertyAction.privilegedGetProperty("java.security.debug");

        String args2 = GetPropertyAction
                .privilegedGetProperty("java.security.auth.debug");

        if (args == null) {
            args = args2;
        } else {
            if (args2 != null)
               args = args + "," + args2;
        }

        if (args != null) {
            args = marshal(args);
            if (args.equals("help")) {
                Help();
            }
        }
    }

    public static void Help()
    {
        System.err.println();
        System.err.println("all           turn on all debugging");
        System.err.println("access        print all checkPermission results");
        System.err.println("certpath      PKIX CertPathBuilder and");
        System.err.println("              CertPathValidator debugging");
        System.err.println("combiner      SubjectDomainCombiner debugging");
        System.err.println("gssloginconfig");
        System.err.println("              GSS LoginConfigImpl debugging");
        System.err.println("configfile    JAAS ConfigFile loading");
        System.err.println("configparser  JAAS ConfigFile parsing");
        System.err.println("jar           jar verification");
        System.err.println("logincontext  login context results");
        System.err.println("jca           JCA engine class debugging");
        System.err.println("keystore      KeyStore debugging");
        System.err.println("policy        loading and granting");
        System.err.println("provider      security provider debugging");
        System.err.println("pkcs11        PKCS11 session manager debugging");
        System.err.println("pkcs11keystore");
        System.err.println("              PKCS11 KeyStore debugging");
        System.err.println("pkcs12        PKCS12 KeyStore debugging");
        System.err.println("sunpkcs11     SunPKCS11 provider debugging");
        System.err.println("scl           permissions SecureClassLoader assigns");
        System.err.println("securerandom  SecureRandom");
        System.err.println("ts            timestamping");
        System.err.println();
        System.err.println("The following can be used with access:");
        System.err.println();
        System.err.println("stack         include stack trace");
        System.err.println("domain        dump all domains in context");
        System.err.println("failure       before throwing exception, dump stack");
        System.err.println("              and domain that didn't have permission");
        System.err.println();
        System.err.println("The following can be used with stack and domain:");
        System.err.println();
        System.err.println("permission=<classname>");
        System.err.println("              only dump output if specified permission");
        System.err.println("              is being checked");
        System.err.println("codebase=<URL>");
        System.err.println("              only dump output if specified codebase");
        System.err.println("              is being checked");
        System.err.println();
        System.err.println("The following can be used with provider:");
        System.err.println();
        System.err.println("engine=<engines>");
        System.err.println("              only dump output for the specified list");
        System.err.println("              of JCA engines. Supported values:");
        System.err.println("              Cipher, KeyAgreement, KeyGenerator,");
        System.err.println("              KeyPairGenerator, KeyStore, Mac,");
        System.err.println("              MessageDigest, SecureRandom, Signature.");
        System.err.println();
        System.err.println("The following can be used with certpath:");
        System.err.println();
        System.err.println("ocsp          dump the OCSP protocol exchanges");
        System.err.println("verbose       verbose debugging");
        System.err.println();
        System.err.println("Note: Separate multiple options with a comma");
        System.exit(0);
    }


    
Get a Debug object corresponding to whether or not the given
option is set. Set the prefix to be the same as option.
/**
     * Get a Debug object corresponding to whether or not the given
     * option is set. Set the prefix to be the same as option.
     */

    public static Debug getInstance(String option)
    {
        return getInstance(option, option);
    }

    
Get a Debug object corresponding to whether or not the given
option is set. Set the prefix to be prefix.
/**
     * Get a Debug object corresponding to whether or not the given
     * option is set. Set the prefix to be prefix.
     */
    public static Debug getInstance(String option, String prefix)
    {
        if (isOn(option)) {
            Debug d = new Debug();
            d.prefix = prefix;
            return d;
        } else {
            return null;
        }
    }

    
True if the system property "security.debug" contains the
string "option".
/**
     * True if the system property "security.debug" contains the
     * string "option".
     */
    public static boolean isOn(String option)
    {
        if (args == null)
            return false;
        else {
            if (args.indexOf("all") != -1)
                return true;
            else
                return (args.indexOf(option) != -1);
        }
    }

    
Check if verbose messages is enabled for extra debugging.
/**
     * Check if verbose messages is enabled for extra debugging.
     */
    public static boolean isVerbose() {
        return isOn("verbose");
    }

    
print a message to stderr that is prefixed with the prefix
created from the call to getInstance.
/**
     * print a message to stderr that is prefixed with the prefix
     * created from the call to getInstance.
     */

    public void println(String message)
    {
        System.err.println(prefix + ": "+message);
    }

    
print a message to stderr that is prefixed with the prefix
created from the call to getInstance and obj.
/**
     * print a message to stderr that is prefixed with the prefix
     * created from the call to getInstance and obj.
     */
    public void println(Object obj, String message)
    {
        System.err.println(prefix + " [" + obj.getClass().getSimpleName() +
                "@" + System.identityHashCode(obj) + "]: "+message);
    }

    
print a blank line to stderr that is prefixed with the prefix.
/**
     * print a blank line to stderr that is prefixed with the prefix.
     */

    public void println()
    {
        System.err.println(prefix + ":");
    }

    
print a message to stderr that is prefixed with the prefix.
/**
     * print a message to stderr that is prefixed with the prefix.
     */

    public static void println(String prefix, String message)
    {
        System.err.println(prefix + ": "+message);
    }

    
PrintStream for debug methods. Currently only System.err is supported.
/**
     * PrintStream for debug methods. Currently only System.err is supported.
     */
    public PrintStream getPrintStream() {
        return System.err;
    }

    
return a hexadecimal printed representation of the specified
BigInteger object. the value is formatted to fit on lines of
at least 75 characters, with embedded newlines. Words are
separated for readability, with eight words (32 bytes) per line.
/**
     * return a hexadecimal printed representation of the specified
     * BigInteger object. the value is formatted to fit on lines of
     * at least 75 characters, with embedded newlines. Words are
     * separated for readability, with eight words (32 bytes) per line.
     */
    public static String toHexString(BigInteger b) {
        String hexValue = b.toString(16);
        StringBuilder sb = new StringBuilder(hexValue.length()*2);

        if (hexValue.startsWith("-")) {
            sb.append("   -");
            hexValue = hexValue.substring(1);
        } else {
            sb.append("    ");     // four spaces
        }
        if ((hexValue.length()%2) != 0) {
            // add back the leading 0
            hexValue = "0" + hexValue;
        }
        int i=0;
        while (i < hexValue.length()) {
            // one byte at a time
            sb.append(hexValue.substring(i, i + 2));
            i+=2;
            if (i!= hexValue.length()) {
                if ((i%64) == 0) {
                    sb.append("\n    ");     // line after eight words
                } else if (i%8 == 0) {
                    sb.append(" ");     // space between words
                }
            }
        }
        return sb.toString();
    }

    
change a string into lower case except permission classes and URLs.
/**
     * change a string into lower case except permission classes and URLs.
     */
    private static String marshal(String args) {
        if (args != null) {
            StringBuilder target = new StringBuilder();
            StringBuffer source = new StringBuffer(args);

            // obtain the "permission=<classname>" options
            // the syntax of classname: IDENTIFIER.IDENTIFIER
            // the regular express to match a class name:
            // "[a-zA-Z_$][a-zA-Z0-9_$]*([.][a-zA-Z_$][a-zA-Z0-9_$]*)*"
            String keyReg = "[Pp][Ee][Rr][Mm][Ii][Ss][Ss][Ii][Oo][Nn]=";
            String keyStr = "permission=";
            String reg = keyReg +
                "[a-zA-Z_$][a-zA-Z0-9_$]*([.][a-zA-Z_$][a-zA-Z0-9_$]*)*";
            Pattern pattern = Pattern.compile(reg);
            Matcher matcher = pattern.matcher(source);
            StringBuffer left = new StringBuffer();
            while (matcher.find()) {
                String matched = matcher.group();
                target.append(matched.replaceFirst(keyReg, keyStr));
                target.append("  ");

                // delete the matched sequence
                matcher.appendReplacement(left, "");
            }
            matcher.appendTail(left);
            source = left;

            // obtain the "codebase=<URL>" options
            // the syntax of URL is too flexible, and here assumes that the
            // URL contains no space, comma(','), and semicolon(';'). That
            // also means those characters also could be used as separator
            // after codebase option.
            // However, the assumption is incorrect in some special situation
            // when the URL contains comma or semicolon
            keyReg = "[Cc][Oo][Dd][Ee][Bb][Aa][Ss][Ee]=";
            keyStr = "codebase=";
            reg = keyReg + "[^, ;]*";
            pattern = Pattern.compile(reg);
            matcher = pattern.matcher(source);
            left = new StringBuffer();
            while (matcher.find()) {
                String matched = matcher.group();
                target.append(matched.replaceFirst(keyReg, keyStr));
                target.append("  ");

                // delete the matched sequence
                matcher.appendReplacement(left, "");
            }
            matcher.appendTail(left);
            source = left;

            // convert the rest to lower-case characters
            target.append(source.toString().toLowerCase(Locale.ENGLISH));

            return target.toString();
        }

        return null;
    }

    public static String toString(byte[] b) {
        if (b == null) {
            return "(null)";
        }
        return HexFormat.ofDelimiter(":").formatHex(b);
    }

}